brcm80211: remove redundant pointer 'address'

Pointer 'address' is being assigned and updated in a few places
by it is never read. Hence the assignments are redundant and can
be removed.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200405133906.381358-1-colin.king@canonical.com